list, set, dict, generator comprehension

list comprehension:

my_list = [num*num for num in range(1,11)]
print(my_list)

if使用

my_list = [num for num in range(1,11) if num > 5]
print(my_list)

if在for循环后面

if else使用

my_list = [num if num < 5 else 'larger' for num in range(1,11) ]
print(my_list)

if在for循环前面

set comprehension与list comprehension类似,区别在于list使用的是[],而set得用()

例如:

my_list = [1,1,1,2,2,3,3,3,3,4,4,7,7,7,9,9,9,9]
my_set = {num for num in my_list}
print(my_set)

结果为:

{1, 2, 3, 4, 7, 9}

dict comprehension:

简单易懂的方法:

names = ['peter', 'clark', 'wade', 'bruce', 'logan']
heros = ['spideman', 'superman', 'deadpool', 'batman', 'wolverine']
my_dict = {}
for name, hero in zip(names, heros):
    my_dict[name] = hero
print(my_dict)

dict comp:

names = ['peter', 'clark', 'wade', 'bruce', 'logan']
heros = ['spideman', 'superman', 'deadpool', 'batman', 'wolverine']
my_dict = {name: hero for name, hero in zip(names, heros)}
print(my_dict)

结果都是:

{'peter': 'spideman', 'clark': 'superman', 'wade': 'deadpool', 'bruce': 'batman', 'logan': 'wolverine'}

generator comprehension:

注意:

上面的list用的是[];

dict用的是{}

set用的也是{},区别是没有:

而generator用的是()

my_gen = (num for num in range(1,11))
for item in my_gen:
    print(item)